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Understanding scala enumerations
...er Value representing the individual elements of the enumeration (it's actually an inner class, but the difference doesn't matter here).
Thus object WeekDay inherits that type member. The line type WeekDay = Value is just a type alias. It is useful, because after you import it elsewhere with import...
What is the difference between Set and List?
...tees about the implementation of the order (and that the order may not be stable between calls, unlike with an ordered list).
– lilbyrdie
Apr 10 '14 at 15:35
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Calling a base class's classmethod in Python
...asses, which derive from object. (at least in Python 2, but in Py3 I think all classes are new-style, IIRC) Otherwise you have to do Base.do(self, ...), I think, thereby hard-coding the name of the superclass.
– David Z
Jun 11 '14 at 19:29
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Format floats with standard json module
...loat class in Tom Wuttke's answer works, but only if %g encoding works globally for your application. The %.15g is a bit magic, it works because float precision is 17 significant digits and %g does not print trailing zeroes.
I spent some time trying to make a PrettyFloat that allowed customization ...
How to properly reuse connection to Mongodb across NodeJs application and modules
...lhost:27017";
var _db;
module.exports = {
connectToServer: function( callback ) {
MongoClient.connect( url, { useNewUrlParser: true }, function( err, client ) {
_db = client.db('test_db');
return callback( err );
} );
},
getDb: function() {
return _db;
}
};
To...
Programmatically get the cache line size?
All platforms welcome, please specify the platform for your answer.
8 Answers
8
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target=“_blank” vs. target=“_new”
...or window when the user clicks on the link.
Using target="_new" is technically invalid according to the specifications, but as far as I know every browser will behave the same way:
it will search for a tab or window with the context name "_new"
if a "_new" tab/window is found, then the URL is loa...
What's the better (cleaner) way to ignore output in PowerShell? [closed]
...ad and > $null has about a 0.3% overhead.
Addendum 2017-10-16: I originally overlooked another option with Out-Null, the use of the -inputObject parameter. Using this the overhead seems to disappear, however the syntax is different:
Out-Null -inputObject ($(1..1000) | ?{$_ -is [int]})
And no...
How to change a PG column to NULLABLE TRUE?
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From the fine manual:
ALTER TABLE mytable ALTER COLUMN mycolumn DROP NOT NULL;
There's no need to specify the type when you're just changing the nullability.
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How to get object length [duplicate]
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This is actually worse than using a simple loop and counter because of the added overhead of the callback function.
– nullability
Feb 19 '13 at 17:35
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